Well, I re-installed XCode 3.0 and then re did the "sudo find / -ls > new_find.txt" to see what files were added.

Macintosh:~ sck$ grep -i "quicktime/quicktime.h" find.txt new_find.txt

find.txt:577661        8 -rw-rw-r--    1 _devdocs wheel         218 May  2  2007 /Developer/Documentation/DocSets/com.apple.ADC_Reference_Library.CoreReference.docset/Contents/Resources/Documents/documentation/QuickTime/QuickTime.html

find.txt:513949        8 lrwxr-xr-x    1 root     wheel          77 Oct 29 23:50 /Developer/SDKs/MacOSX10.4u.sdk/Developer/Headers/CFMCarbon/QuickTime/QuickTime.h -> ../../../../System/Library/Frameworks/QuickTime.framework/Headers/QuickTime.h
new_find.txt:4102117        8 -rw-rw-r--    1 _devdocs wheel         218 May  2  2007 /Developer/Documentation/DocSets/com.apple.ADC_Reference_Library.CoreReference.docset/Contents/Resources/Documents/documentation/QuickTime/QuickTime.html
new_find.txt:4119621        8 lrwxr-xr-x    1 root     wheel          77 Dec 23 07:34 /Developer/SDKs/MacOSX10.3.9.sdk/Developer/Headers/CFMCarbon/QuickTime/QuickTime.h -> ../../../../System/Library/Frameworks/QuickTime.framework/Headers/QuickTime.h
new_find.txt:4038650        8 lrwxr-xr-x    1 root     wheel          77 Dec 23 07:31 /Developer/SDKs/MacOSX10.4u.sdk/Developer/Headers/CFMCarbon/QuickTime/QuickTime.h -> ../../../../System/Library/Frameworks/QuickTime.framework/Headers/QuickTime.h
Macintosh:~ sck$

So, according to find, there's only the new 10.3 sdk file added...

Originally when I did the XCode install I did not install WebObjects or 10.3 SDK, but this time I installed everything and it worked...

So, officially, I don't understand, but I comply and am happy... :)